1. Field of the Invention
The present invention relates to trailer hitches for all terrain vehicles and off-road vehicles. More specifically, the present invention pertains to an adjustable trailer hitch having a pair of universal joints that allow improved handling of a trailer behind an off-road vehicle while navigating uneven terrain or during tight turn maneuvers.
Trailer hitches are mechanical assemblies that permit the connection of a trailer to a vehicle using a specific type of coupling. Most car and truck receiver hitches involve a ball joint that connects a trailer shaft to a ball joint extending from a receiver assembly that is attached to the vehicle frame. This connection allows relative rotation between the trailer and the lead vehicle about the ball joint location, which commonly occurs over changing road surfaces and any relative movement between the trailer and vehicle suspensions. Motorcycle and all terrain vehicle (ATV) trailer attachment systems commonly involve greater pivotal capability, wherein motorcycle hitches in particular must allow the motorcycle to lean during turns and maneuvers, wherein the motorcycle leans independently of the trailer to ensure stability during turns. Both of these hitch types involve a single universal joint that allows rotation and pivoting of the joint about a single joint location.
Problems arise when deploying such joints on an ATV and off-road vehicle, as these vehicle types are not restricted to smooth roadway surfaces. Traversing off-road terrain or navigating through undeveloped land can expose the trailer and lead vehicle to relative pitching and rotation, which places considerable load on the hitch if sufficient freedom of movement and rotation is not provided. A further issue associated with ATV trailer hitches is the ability to navigate within tight spaces, for instance between trees and rocks during an off-road venture. The ability to make tight turns without binding or maxing out the free rotation/pivoting of the hitch joint is of prime importance for vehicle stability, off-road capability and further the integrity of the components. If a turn is taken too sharply while traveling over an uneven surface, the trailer hitch will be subjected to considerable load that can cause failure of the joint, or even cause the trailer itself to tip on its side. This situation creates a hazard for the user, as damage to the trailer hitch may be without remedy in desolate areas, and tipping of the trailer puts both the trailer and the lead vehicle in danger of rolling over. If one side of the trail lifts off of the ground, spilling or tumbling supplies can result, as well as expose the assembly and the vehicles to damage.
The present invention provides a new and improved ATV hitch that utilizes an adjustable driveshaft length to offset the trailer from a lead vehicle, while also providing increased freedom of movement with respect to the trailer and lead vehicle by incorporating a first and second pivotal joint at the ends of the driveshaft. This increased freedom and offset provides a means to traverse extreme off-road surface irregularities and navigate between confined areas that require a tight turning radius. Each universal joint utilizes a first and second yoke, where the outer yoke is fixed to either the lead vehicle or the trailer, and the inner yoke is permitted to rotate thereabout. The trailer yoke is further rotatably connected to the trailer frame to allow the system to permit yawing, pitching and rolling of the trailer with respect to the lead vehicle without binding. Overall, the system provides improved handling and mobility when attaching a trailer to an off-road vehicle such as an all terrain vehicle.
2. Description of the Prior Art
Devices have been disclosed in the prior art that relate to trailer hitches and ATV hitch assemblies. These include devices that have been patented and published in patent application publications, and generally relate to trailer hitches for ATVs with limited articulation capability or a single universal joint connection. The forgoing is a list of devices deemed most relevant to the present disclosure, which are herein described for the purposes of highlighting and differentiating the unique aspects of the present invention, and further highlighting the drawbacks existing in the prior art.
Specifically, U.S. Pat. No. 6,378,904 to Niehoff discloses a trailer that is adapted to be hitched to an all terrain vehicle to haul cargo. The trailer includes a tubular frame and tongue attachable to a ball hitch mounted to the lead vehicle. This provides a direct connection with the trailer hitch of the lead vehicle and a standard ball hitch attachment, which provides adequate relative motion for even terrain, however lacks the ability to heavily articulate around tight turns or react to extremely uneven terrain without causing dislodgment or damage to the hitch assembly.
Similar to the Niehoff device is U.S. Pat. No. 7,229,090 to Cumbie, which discloses a folding trailer for attachment to an all terrain vehicle trailer hitch. The tongue of the hitch attachment is enable to pivot the trailer from a horizontal to a vertical position, as desired by the user. The connection to the trailer hitch of the ATV is one that includes an elongated and tubular connection that does not permit relative rotation when deployed. The lack of rotational freedom limits the terrain upon which the assembly may deployed without overly loading the hitch assembly, particularly when considering very uneven terrain or tight quarters mobility between obstacles.
U.S. Pat. No. 7,938,431 to Snyder is another such device that discloses a swivel type hitch for an all terrain vehicle, wherein a universal joint is positioned between the vehicle and the trailer for improved freedom of movement. The device comprises universal joint, a spindle attached to the universal joint, a slideable sleeve placed onto the spindle, while the sleeve is attached to the tongue of the trailer. A plurality of plates attach to the sleeve to limit rotation of the trailer and reinforce the structure while in use. While the Snyder device discloses a trailer hitch for an ATV using a universal joint for improved relative rotation, the use of a single joint limits the turning radius of the hitch and further the allowable motion of the trailer with respect to the vehicle while on severely uneven terrain. The present invention utilizes a pair of pivotal and rotatable joints connected by a slideable driveshaft connection, providing a setup having an offset between pivot and rotation points that separate movement between the vehicle and the trailer. This prevents binding at extreme angles during maneuvering or traversing uneven terrain.
Finally, U.S. Pat. No. 4,548,423 to Craven discloses a similar trailer hitch setup as the Snyder device, wherein a universal joint is positioned between a split block and a bearing block for connecting a trailer to a vehicle and providing horizontal and vertical pivotal movement and longitudinal rotation thereof. The split block provides an openable block that sandwiches a pin of one yoke of the universal joint for quick connection and disengagement between the two, while a pin from a second yoke connects through a bearing block and is secured by a pair of locking nuts to prevent dislodgment. Similar to the Snyder device, the range of rotation at severe angles is limited with a universal joint, while a multiple, separated joint setup provides improved clearance for turning, a means to prevent binding at extreme vehicle turn angles, and further extreme rotational angles over uneven terrain, all while the trailer and vehicle maintain contact with the ground during the maneuver.
The present invention provides an articulating trailer hitch attachment that is particularly suited for use with ATVs and off-road vehicles. The design of the assembly is one that allows articulation of the trailer in the way of pitching, rolling and yawing with respect to the lead vehicle during deployment. The ends of the assembly are securely fastened to the lead vehicle and trailer, while a first pivotal joint and second pivotal rotation joint are provided to allow movement of the trailer over obstacles and through tight spaces when traveling off-road. It is submitted that the present invention is substantially divergent in design elements from the prior art, and consequently it is clear that there is a need in the art for an improvement to existing off-road trailer attachment systems. In this regard the instant invention substantially fulfills these needs.